Test G FORD MUSTANG 2003 Manual Online

PINPOINT TEST C: BRAKE LOCKUP DURING LIGHT BRAKE PEDAL
FORCE z
Is the resistance greater than 10,000 ohms? No
REPAIR the ground short in
circuit 128 (VT/YE). TEST the
system for normal operation.
B6 CHECK DAYTIME RUNNING LIGHTS (DRL) MODULE
z
Disconnect: DRL Module C1030.
z Measure the resistance to ground at C124- 2.
z Is the resistance greater than 10,000 ohms? Yes
REPAIR the DRL module. TEST
the system for normal operation.
No
REPAIR the ground short in
circuit 22 (LB/BK) or 977
(VT/WH). TEST the system for
normal operation.
Test Step Result / Action to Take
C1 INSPECT THE TIRES
z
Inspect the tires for uneven or excessive
wear, correct pressure, correct size and
type.
z Are the tires OK? Yes
GO to
C2 .
No
CORRECT as necessary. RETEST for
normal operation. C2 CHECK THE BRAKE CALIPER
COMPONENTS z
Inspect the brake pads and brake discs for
wear, damage, contamination and correct
installation.
z Are the brake components OK? Yes
GO to
C3 .
No
CORRECT as necessary. RETEST for
normal operation. C3 CHECK THE PROPORTIONING VALVE
z
Install the gauges from the ABS brake and
pressure test kit on one front and one rear
bleeder screw.
z Apply 6895 kPa (1000 psi) to the front
brake system.
z Is the pressure in the rear system 3516- Yes
INSPECT the disc brake calipers and
INSTALL new calipers as necessary.
RETEST for normal operation.
No Klj . 9 ba
152003 Mustang Workshop Manual
17. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_4464/S3B~us~en~ ...

PINPOINT TEST D: EXCESSIVE/ERRATIC BRAKE PEDAL TRAVEL
PINPOINT TEST E: HYDRO-
BOOST, NO POWER ASSIST 4481 kPa (510-
650 psi)? INSTALL a new proportioning valve.
RETEST for normal operation.
Test Step Result / Action to Take
D1 CHECK FOR SPONGY PEDAL
z
Key in ON position.
z Operate the brake pedal and note pedal feel.
z Does the pedal feel spongy? Yes
BLEED the brake system. REFER to
Bleeding —
System in this section.
RETEST for normal operation.
No
GO to D2 .
D2 CHECK THE BRAKE PEDAL
z
Inspect the brake pedal and bracket for
binding, obstruction or damage.
z Is the brake pedal OK? Yes
GO to
D3 .
No
REPAIR or INSTALL a new brake pedal as
necessary. RETEST for normal operation. D3 CHECK THE BRAKE COMPONENTS
z
Inspect the calipers bolts, anchor plate bolts
and anti- rattle springs for binding, damage,
contamination and correct installation.
z Are the bolts and springs OK? Yes
GO to
D4 .
No
REPAIR or INSTALL new components as
necessary. RETEST for normal operation. D4 CHECK THE BOOSTER AND MASTER
CYLINDER z
Check the power brake booster and brake
master cylinder for correct installation and
correct push rod adjustment. Refer to
Section 206 - 06 and to Section 206 - 07 .
z Are the power brake booster and the
brake master cylinder OK? Yes
INSPECT the front wheel bearings for
wear, damage and correct installation and
the rear axle end play. CORRECT as
necessary. RETEST for normal operation.
No
CORRECT as necessary. RETEST for
normal operation.
Test Step Result / Action to Take
E1 CHECK FLUID LEVEL IN POWER STEERING
PUMP z
Check fluid level in power steering pump.
z Is level within specification? Yes
GO to
E2 .
No
CHECK for leakage of power steering
fluid. ADD fluid as necessary. E2 CHECK ACCESSORY DRIVE BELT Klj . 10 ba
152003 Mustang Workshop Manual
17. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_4464/S3B~us~en~ ...

PINPOINT TEST F: HYDRO-
BOOST ERRATIC OPERATION, STICKS,
BINDS OR GRABS z
Check accessory drive belt tension and
condition. Refer to Section 303 - 05 .
z Is the accessory drive belt OK? Yes
GO to
E3 .
No
INSTALL a new accessory drive belt.
REFER to Section 303 - 05 .
E3 CHECK POWER STEERING HOSES
z
Check power steering pressure hoses, power
steering gear pressure hoses and power
steering return hose for cracks or leaks.
z Do power steering pressure hose, power
steering gear hose and power steering
return hose check OK? Yes
GO to
E4 .
No
INSTALL new hoses as necessary.
REFER to Section 211 - 00 .
E4 CHECK BRAKE PEDAL LINKAGE
z
Check brake pedal linkage for binding or
sticking operation.
z Does pedal linkage check OK? Yes
GO to
E5 .
No
INSTALL new pedal linkage as necessary.
REFER to Section 206 - 06 .
E5 CHECK POWER STEERING PUMP SPEED
z
Check engine idle speed against
specifications.
z Is engine idle speed OK? Yes
GO to
E6 .
No
SET engine idle speed to specification.
REFER to Powertrain Control/Emissions
Diagnosis (PC/ED) manual. E6 CHECK FOR PLUGGED RETURN HOSE
z
NOTE: The return hose from the oil cooler to
the power steering reservoir has an in- line
filter in the hose.
z Disconnect power steering return hose from
power steering fluid cooler and power
steering pump reservoir.
z Pass air through hose from the oil cooler end.
z Is hose plugged? Yes
INSTALL a new power steering return
hose.
No
GO to
E7 .
E7 CHECK POWER STEERING PUMP FLOW
AND RELIEF z
Test power steering pump for correct flow
and relief pressure. Refer to Section 211 - 00 .
z Is power steering pump operating
correctly? Yes
INSTALL a new power brake hydro-
boost
unit. REFER to Section 206 - 07 .
No
INSTALL a new power steering pump.
REFER to Section 211 - 02 .
Test Step Result / Action to
Take F1 CHECK SUPPLY HOSE
z
Check for obstructions in power steering return hose and Yes Klj . 11 ba
152003 Mustang Workshop Manual
17. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_4464/S3B~us~en~ ...

PINPOINT TEST G: HYDRO-
BOOST BRAKE SYSTEM OPERATION
SUSPECT connections between the power steering pump reservoir and
between the power steering pump reservoir and the hydro-
boost
power brake booster.
z Are there any obstructions? REMOVE
obstructions or
INSTALL a new
hose.
No
GO to
F2 .
F2 CHECK BOOSTER OPERATION
z
Have an assistant check the fluid in the power steering pump
reservoir while rapidly applying the brake pedal approximately one
inch.
z Does the fluid show any movement or spouting? Yes
System OK.
No
INSTALL a new
hydro-boost
assembly. Test Step Result / Action to Take
G1 CHECK BASIC OPERATION
z
Key in OFF position.
z Press and release brake pedal several times to deplete all
hydraulic pressure from the hydro- boost power brake
booster.
z Press and hold brake pedal with light pressure.
z Key in START position.
z Does the brake pedal fall slightly and hold, and is less
pressure now required to hold brake pedal at the new
position? Yes
Hydro-
boost is OK.
No
GO to G2 .
G2 CHECK FOR HYDRAULIC BRAKE LEAK
z
With engine running, press and release brake pedal several
times.
z Hold brake pedal down with medium pressure, 34- 47 Nm
(25- 35 lb- ft).
z Does brake pedal move toward floor? Yes
GO to
G3 .
No
GO to G4 .
G3 CHECK FOR LEAKS —
BRAKE FLUID LINES z
Check for leaks at brake lines, including brake master
cylinder and brake hose.
z Do components check OK? Yes
COMPLETE master cylinder
By-
Pass Condition Test in
this section.
No
INSTALL new hoses and
lines as necessary. G4 CHECK HYDRO-
BOOST CONNECTIONS z
Clean the hydro- boost power brake booster, power steering
pressure hose, power steering gear pressure hose and
power steering return hose and connection.
z Start engine and run at idle.
z Check hose connections for leakage.
z Do hose connections check OK? Yes
GO to
G5 .
No
REPAIR or INSTALL new
hose and connections as
necessary. G5 CHECK FOR HYDRO-
BOOST LEAK Klj . 12 ba
152003 Mustang Workshop Manual
17. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_4464/S3B~us~en~ ...

Component Tests
Brake Booster
1. Check the hydraulic brake system for leaks or insufficient fluid.
2. With the transmission (7003) in NEUTRAL, stop the engine (6007) and apply the parking brake control (2780). Apply the brake pedal several times to exhaust all vacuum in the system.
3. Apply the brake pedal and hold it in the applied position. Start the engine. If the vacuum system is operating, the brake pedal will tend to move downward under constant foot pressure. If no
motion is felt, the power brake booster system is not functioning. Continue with the following
steps.
4. Remove the vacuum booster hose from the check valve connection. Manifold vacuum must be available at the check valve end of the vacuum booster hose with the engine at idle speed and
the transmission in NEUTRAL. If the manifold vacuum is available to the power brake booster,
connect the vacuum booster hose to the power brake booster check valve and repeat Steps 2
and 3.
5. If no downward movement of the brake pedal is felt, install a new power brake booster.
6. Operate the engine a minimum of 10 seconds at fast idle. Stop the engine, and let the vehicle stand for 10 minutes. Then apply the brake pedal with approximately 89 N (20 lb) of force. The
brake pedal feel should be the same as that noted with the engine operating. If the brake pedal
feels hard (no power assist), install a new power brake booster check valve and retest. If the
brake pedal feels spongy, bleed the hydraulic system to remove air. For additional information,
refer to Bleeding — System in this section. Check Valve z
Engine running at idle speed.
z CAUTION: Do not hold the brake pedal at 444 Nm
(100 lb) force for more than 5 seconds at a time.
z Apply brake pedal with approximately 444 Nm (100 lb)
force and hold.
z Check hydro-boost unit input seal, housing seal,
accumulator seal, piston seal and spool plug seal for
leakage.
z Is hydro- boost unit free of leaks? Yes
GO to
G6 .
No
INSTALL a new hydro- boost
unit. G6 CHECK RESERVE RETENTION
z
Engine running at idle speed.
z CAUTION: Do not hold the brake pedal at 444 Nm
(100 lb) force for more than 5 seconds at a time.
z Charge system to pressure by holding the steering wheel at
stop or by pressing the brake pedal with approximately 444
Nm (100 lb) force.
z Key in OFF position.
z Wait five seconds.
z Press brake pedal and observe if there is any power brake
reserve.
z Is there any power brake reserve? Yes
Hydro-
boost unit is OK.
No
INSTALL a new hydro- boost
unit. Klj . 13 ba
152003 Mustang Workshop Manual
17. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_4464/S3B~us~en~ ...

The function of the power brake booster check valve is to allow manifold vacuum to enter the power
brake booster and prevent the escape of vacuum in case manifold vacuum is lost during sustained full
throttle operation.
To test the function of the power brake booster check valve :
zStart and run the engine for at least 10 seconds.
z Operate the brake pedal to check for power assist.
z Disconnect the vacuum booster hose from the power brake booster check valve. Do not remove
the power brake booster check valve from the power brake booster.
z There should be enough vacuum retained in the brake booster for at least one more power-
assisted brake operation.
Brake Master Cylinder — Normal Conditions
The following conditions are considered normal and are not indications that the brake master cylinder
is in need of service.
Condition 1: During normal operation of the brake master cylinder, the fluid level in the brake master
cylinder reservoir will rise during brake application and fall during release. The net fluid level (i.e., after
brake application and release) will remain unchanged.
Condition 2: A trace of brake fluid will exist on the booster shell below the master cylinder mounting
flange. This results from the normal lubricating action of the master cylinder bore and seal.
Condition 3: Fluid level will decrease with pad wear.
Brake Master Cylinder — Abnormal Conditions
Changes in brake pedal feel or travel are indicators that something could be wrong in the brake
system. GO to Symptom Chart for abnormal condition diagnosis.
Bypass Condition Test 1. Disconnect the brake lines at the brake master cylinder.
2. Plug the outlet ports of the brake master cylinder.
3. Apply the brakes. If brake pedal height cannot be maintained, the brake master cylinder has an internal leak and must be rebuilt or replaced.
Compensator Port Check
The purpose of the compensator ports in the brake master cylinder is to supply any additional brake
fluid required by the system due to brake pad wear and to allow brake fluid returning from the brake
lines to the brake master cylinder to enter the brake master cylinder reservoir.
The returning brake fluid will cause a slight turbulence in the brake master cylinder reservoir. Klj . 14 ba
152003 Mustang Workshop Manual
17. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_4464/S3B~us~en~ ...

GENERAL PROCEDURES
Bleeding —
Components
Master Cylinder Priming — In-Vehicle or Bench
WARNING: Brake fluid contains polyglycol ethers and polyglycols. Avoid contact with
eyes. Wash hands thoroughly after handling. If brake fluid contacts eyes, flush eyes with
running water for 15 minutes. Get medical attention if irritation persists. If taken internally,
drink water and induce vomiting. Get medical attention immediately.
CAUTION: Do not allow the brake master cylinder reservoir to run dry during the bleeding
operation. Keep the brake master cylinder reservoir filled with the specified brake fluid. Never
reuse the brake fluid that has been drained from the hydraulic system.
CAUTION: Brake fluid is harmful to painted and plastic surfaces. If brake fluid is spilled
onto a painted or plastic surface, immediately wash it with water.
NOTE: When any part of the hydraulic system has been disconnected for repair or installation of new
components, air can enter the system and cause spongy brake pedal (2455) action. This requires
bleeding of the hydraulic system after it has been correctly connected. The hydraulic system can be
bled manually or with pressure bleeding equipment.
NOTE: When a new brake master cylinder (2140) has been installed or the system has been emptied,
or partially emptied, it should be primed to prevent air from entering the system.
1. For in- vehicle priming, disconnect the brake lines.
SECTION 206-
00: Brake System — General Information 2003 Mustang Workshop Manual Special Tool(s)
Worldwide Diagnostic System
(WDS)
418-
F224,
New Generation STAR (NGS)
Tester
418- F052, or equivalent scan
tool NGS Flash Cable
418-
F120 (007- 00531) or
Equivalent Klj . 1 ba
62003 Mustang Workshop Manual
17. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_4464/S3B~us~en~ ...

DIAGNOSIS AND TESTING
Parking Brake
Inspection and Verification
1. Verify the customer's concern by operating the parking brake system to duplicate the condition.
2. Inspect to determine if one of the following mechanical or electrical concerns apply:
3. If the inspection reveals obvious concern(s) that can be readily identified, service as necessary.
4. If concern(s) remains after the inspection, determine the symptoms. GO to Symptom Chart .
Symptom Chart
Pinpoint Tests
PINPOINT TEST A: PARKING BRAKE WILL NOT APPLY SECTION 206-
05: Parking Brake and Actuation 2003 Mustang Workshop Manual Visual Inspection Chart
Mechanical Electrical
z
Damaged parking brake control
z Binding/damaged parking brake cables z
Parking brake signal switch
Symptom Chart Condition
Possible Sources Action
z Parking Brake Will Not
Apply z
Parking brake
control.
z Parking brake
cable. z
Go To Pinpoint Test A .
z Parking Brake Will Not
Release z
Parking brake
cable.
z Parking brake
control. z
Go To Pinpoint Test B .
Test Step Result / Action to Take
A1 CHECK THE PARKING BRAKE
CABLES z
Raise and support the vehicle. Refer Yes Klj . 1 ba
32003 Mustang Workshop Manual
17. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_4464/S3B~us~en~ ...

PINPOINT TEST B: PARKING BRAKE WILL NOT RELEASE to Section 100 - 02 .
z Inspect for broken or binding parking
brake cables or broken guide clips.
z Is there a parking brake cable
concern? INSTALL a new parking brake cable as
necessary. TEST the system for normal
operation.
No
GO to
A2 .
A2 CHECK THE PARKING BRAKE
CONTROL z
Operate the parking brake control.
z Does the parking brake control
operate smoothly? Yes
INSTALL a new parking brake lever. RESTORE
vehicle and TEST the system for normal
operation.
No
REPAIR the binding condition in the parking brake
control. TEST the system for normal operation.
Test Step Result / Action to Take
B1 CHECK PARKING BRAKE CONTROL
z
Raise and support the vehicle. Refer to
Section 100 - 02 .
z Release parking brake by pulling
upward on hand lever and pushing
release button.
z Did parking brake release? Yes
GO to
B2 .
No
INSTALL a new parking brake control.
RESTORE the vehicle and TEST the system for
normal operation. B2 CHECK PARKING BRAKE CABLES
z
Loosen tensioner. Refer to Parking Brake Cable Tension Release in this
section.
z Move the gearshift lever to NEUTRAL
position.
z Rotate rear wheels by hand.
z Did rear wheels turn freely? Yes
GO to
B3 .
No
INSTALL new parking brake cables. RESTORE
the vehicle and TEST the system for normal
operation. B3 CHECK REAR PARKING BRAKE
LEVERS z
Disconnect parking brake levers one at
a time.
z Rotate wheel affected by disconnected
parking brake lever.
z Did wheel turn freely? Yes
INSTALL a new parking brake lever. RESTORE
vehicle and TEST the system for normal
operation.
No
REPAIR or INSTALL a new rear brake
component if worn or damaged. TEST the
system for normal operation. Klj . 2 ba
32003 Mustang Workshop Manual
17. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_4464/S3B~us~en~ ...

DIAGNOSIS AND TESTING
Anti-
Lock Control
Refer to Wiring Diagrams Cell 42 , Anti-
Lock Brake for schematic and connector information.
Principles of Operation
The anti- lock brake control module receives wheel speed readings from each anti- lock brake sensor
and processes this information to determine if an ABS event is necessary. The anti- lock brake sensor
electrically senses each tooth of the anti- lock brake sensor indicators as it passes through the anti- lock
brake sensor's magnetic field.
The anti- lock brake control module continuously monitors and compares the rotational speed of each
wheel, and when it detects an impending wheel lock, modulates hydraulic brake pressure to the
appropriate brake caliper. This is accomplished by the anti- lock brake control module triggering the
hydraulic control unit (HCU) to open and close the appropriate solenoid valves. Once the affected
wheel returns to normal speed, the anti- lock brake control module returns the solenoid valves to their
normal position, and normal (base) braking resumes.
The anti- lock brake control module is self- monitoring. When the ignition switch is turned to the RUN
position, the anti- lock brake control module will do a preliminary electrical check, and at approximately
12 km/h (8 mph) the pump motor is turned on for approximately one half- second. Any malfunction of
the ABS will cause the ABS to shut off and the yellow ABS warning indicator to illuminate, however,
normal power assisted braking remains.
The ABS control module has the ability to store multiple DTCs in memory.
Inspection and Verification
1. Verify the customer concern by operating the system.
2. Visually inspect for obvious signs of mechanical and electrical damage.
SECTION 206-
09A: Anti-Lock Control — Rear 2003 Mustang Workshop Manual Special Tool(s)
Worldwide Diagnostic System
(WDS)
418-
F224,
New Generation STAR (NGS)
Tester
418- F052, or equivalent scan
tool 73 Digital Multimeter or
equivalent
105-
R0051 Klj . 1 ba
162003 Mustang Workshop Manual
17. 11. 2011file:///C:/Ford/2000 - 2004/tsocache/SHEF_4464/S3B~us~en~ ...